mirror of
https://github.com/git/git
synced 2024-08-27 11:39:22 +00:00
475 lines
10 KiB
C
475 lines
10 KiB
C
#include "cache.h"
|
|
#include "tag.h"
|
|
#include "commit.h"
|
|
#include "tree.h"
|
|
#include "blob.h"
|
|
#include "tree-walk.h"
|
|
|
|
static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
|
|
{
|
|
struct alternate_object_database *alt;
|
|
char hex[40];
|
|
int found = 0;
|
|
static struct alternate_object_database *fakeent;
|
|
|
|
if (!fakeent) {
|
|
const char *objdir = get_object_directory();
|
|
int objdir_len = strlen(objdir);
|
|
int entlen = objdir_len + 43;
|
|
fakeent = xmalloc(sizeof(*fakeent) + entlen);
|
|
memcpy(fakeent->base, objdir, objdir_len);
|
|
fakeent->name = fakeent->base + objdir_len + 1;
|
|
fakeent->name[-1] = '/';
|
|
}
|
|
fakeent->next = alt_odb_list;
|
|
|
|
sprintf(hex, "%.2s", name);
|
|
for (alt = fakeent; alt && found < 2; alt = alt->next) {
|
|
struct dirent *de;
|
|
DIR *dir;
|
|
sprintf(alt->name, "%.2s/", name);
|
|
dir = opendir(alt->base);
|
|
if (!dir)
|
|
continue;
|
|
while ((de = readdir(dir)) != NULL) {
|
|
if (strlen(de->d_name) != 38)
|
|
continue;
|
|
if (memcmp(de->d_name, name + 2, len - 2))
|
|
continue;
|
|
if (!found) {
|
|
memcpy(hex + 2, de->d_name, 38);
|
|
found++;
|
|
}
|
|
else if (memcmp(hex + 2, de->d_name, 38)) {
|
|
found = 2;
|
|
break;
|
|
}
|
|
}
|
|
closedir(dir);
|
|
}
|
|
if (found == 1)
|
|
return get_sha1_hex(hex, sha1) == 0;
|
|
return found;
|
|
}
|
|
|
|
static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
|
|
{
|
|
do {
|
|
if (*a != *b)
|
|
return 0;
|
|
a++;
|
|
b++;
|
|
len -= 2;
|
|
} while (len > 1);
|
|
if (len)
|
|
if ((*a ^ *b) & 0xf0)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int find_short_packed_object(int len, const unsigned char *match, unsigned char *sha1)
|
|
{
|
|
struct packed_git *p;
|
|
unsigned char found_sha1[20];
|
|
int found = 0;
|
|
|
|
prepare_packed_git();
|
|
for (p = packed_git; p && found < 2; p = p->next) {
|
|
unsigned num = num_packed_objects(p);
|
|
unsigned first = 0, last = num;
|
|
while (first < last) {
|
|
unsigned mid = (first + last) / 2;
|
|
unsigned char now[20];
|
|
int cmp;
|
|
|
|
nth_packed_object_sha1(p, mid, now);
|
|
cmp = memcmp(match, now, 20);
|
|
if (!cmp) {
|
|
first = mid;
|
|
break;
|
|
}
|
|
if (cmp > 0) {
|
|
first = mid+1;
|
|
continue;
|
|
}
|
|
last = mid;
|
|
}
|
|
if (first < num) {
|
|
unsigned char now[20], next[20];
|
|
nth_packed_object_sha1(p, first, now);
|
|
if (match_sha(len, match, now)) {
|
|
if (nth_packed_object_sha1(p, first+1, next) ||
|
|
!match_sha(len, match, next)) {
|
|
/* unique within this pack */
|
|
if (!found) {
|
|
memcpy(found_sha1, now, 20);
|
|
found++;
|
|
}
|
|
else if (memcmp(found_sha1, now, 20)) {
|
|
found = 2;
|
|
break;
|
|
}
|
|
}
|
|
else {
|
|
/* not even unique within this pack */
|
|
found = 2;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (found == 1)
|
|
memcpy(sha1, found_sha1, 20);
|
|
return found;
|
|
}
|
|
|
|
#define SHORT_NAME_NOT_FOUND (-1)
|
|
#define SHORT_NAME_AMBIGUOUS (-2)
|
|
|
|
static int find_unique_short_object(int len, char *canonical,
|
|
unsigned char *res, unsigned char *sha1)
|
|
{
|
|
int has_unpacked, has_packed;
|
|
unsigned char unpacked_sha1[20], packed_sha1[20];
|
|
|
|
has_unpacked = find_short_object_filename(len, canonical, unpacked_sha1);
|
|
has_packed = find_short_packed_object(len, res, packed_sha1);
|
|
if (!has_unpacked && !has_packed)
|
|
return SHORT_NAME_NOT_FOUND;
|
|
if (1 < has_unpacked || 1 < has_packed)
|
|
return SHORT_NAME_AMBIGUOUS;
|
|
if (has_unpacked != has_packed) {
|
|
memcpy(sha1, (has_packed ? packed_sha1 : unpacked_sha1), 20);
|
|
return 0;
|
|
}
|
|
/* Both have unique ones -- do they match? */
|
|
if (memcmp(packed_sha1, unpacked_sha1, 20))
|
|
return SHORT_NAME_AMBIGUOUS;
|
|
memcpy(sha1, packed_sha1, 20);
|
|
return 0;
|
|
}
|
|
|
|
static int get_short_sha1(const char *name, int len, unsigned char *sha1,
|
|
int quietly)
|
|
{
|
|
int i, status;
|
|
char canonical[40];
|
|
unsigned char res[20];
|
|
|
|
if (len < MINIMUM_ABBREV)
|
|
return -1;
|
|
memset(res, 0, 20);
|
|
memset(canonical, 'x', 40);
|
|
for (i = 0; i < len ;i++) {
|
|
unsigned char c = name[i];
|
|
unsigned char val;
|
|
if (c >= '0' && c <= '9')
|
|
val = c - '0';
|
|
else if (c >= 'a' && c <= 'f')
|
|
val = c - 'a' + 10;
|
|
else if (c >= 'A' && c <='F') {
|
|
val = c - 'A' + 10;
|
|
c -= 'A' - 'a';
|
|
}
|
|
else
|
|
return -1;
|
|
canonical[i] = c;
|
|
if (!(i & 1))
|
|
val <<= 4;
|
|
res[i >> 1] |= val;
|
|
}
|
|
|
|
status = find_unique_short_object(i, canonical, res, sha1);
|
|
if (!quietly && (status == SHORT_NAME_AMBIGUOUS))
|
|
return error("short SHA1 %.*s is ambiguous.", len, canonical);
|
|
return status;
|
|
}
|
|
|
|
const char *find_unique_abbrev(const unsigned char *sha1, int len)
|
|
{
|
|
int status, is_null;
|
|
static char hex[41];
|
|
|
|
is_null = !memcmp(sha1, null_sha1, 20);
|
|
memcpy(hex, sha1_to_hex(sha1), 40);
|
|
if (len == 40)
|
|
return hex;
|
|
while (len < 40) {
|
|
unsigned char sha1_ret[20];
|
|
status = get_short_sha1(hex, len, sha1_ret, 1);
|
|
if (!status ||
|
|
(is_null && status != SHORT_NAME_AMBIGUOUS)) {
|
|
hex[len] = 0;
|
|
return hex;
|
|
}
|
|
if (status != SHORT_NAME_AMBIGUOUS)
|
|
return NULL;
|
|
len++;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int ambiguous_path(const char *path, int len)
|
|
{
|
|
int slash = 1;
|
|
int cnt;
|
|
|
|
for (cnt = 0; cnt < len; cnt++) {
|
|
switch (*path++) {
|
|
case '\0':
|
|
break;
|
|
case '/':
|
|
if (slash)
|
|
break;
|
|
slash = 1;
|
|
continue;
|
|
case '.':
|
|
continue;
|
|
default:
|
|
slash = 0;
|
|
continue;
|
|
}
|
|
break;
|
|
}
|
|
return slash;
|
|
}
|
|
|
|
static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
|
|
{
|
|
static const char *fmt[] = {
|
|
"%.*s",
|
|
"refs/%.*s",
|
|
"refs/tags/%.*s",
|
|
"refs/heads/%.*s",
|
|
"refs/remotes/%.*s",
|
|
"refs/remotes/%.*s/HEAD",
|
|
NULL
|
|
};
|
|
const char **p;
|
|
const char *warning = "warning: refname '%.*s' is ambiguous.\n";
|
|
char *pathname;
|
|
int already_found = 0;
|
|
unsigned char *this_result;
|
|
unsigned char sha1_from_ref[20];
|
|
|
|
if (len == 40 && !get_sha1_hex(str, sha1))
|
|
return 0;
|
|
|
|
/* Accept only unambiguous ref paths. */
|
|
if (ambiguous_path(str, len))
|
|
return -1;
|
|
|
|
for (p = fmt; *p; p++) {
|
|
this_result = already_found ? sha1_from_ref : sha1;
|
|
pathname = git_path(*p, len, str);
|
|
if (!read_ref(pathname, this_result)) {
|
|
if (warn_ambiguous_refs) {
|
|
if (already_found)
|
|
fprintf(stderr, warning, len, str);
|
|
already_found++;
|
|
}
|
|
else
|
|
return 0;
|
|
}
|
|
}
|
|
if (already_found)
|
|
return 0;
|
|
return -1;
|
|
}
|
|
|
|
static int get_sha1_1(const char *name, int len, unsigned char *sha1);
|
|
|
|
static int get_parent(const char *name, int len,
|
|
unsigned char *result, int idx)
|
|
{
|
|
unsigned char sha1[20];
|
|
int ret = get_sha1_1(name, len, sha1);
|
|
struct commit *commit;
|
|
struct commit_list *p;
|
|
|
|
if (ret)
|
|
return ret;
|
|
commit = lookup_commit_reference(sha1);
|
|
if (!commit)
|
|
return -1;
|
|
if (parse_commit(commit))
|
|
return -1;
|
|
if (!idx) {
|
|
memcpy(result, commit->object.sha1, 20);
|
|
return 0;
|
|
}
|
|
p = commit->parents;
|
|
while (p) {
|
|
if (!--idx) {
|
|
memcpy(result, p->item->object.sha1, 20);
|
|
return 0;
|
|
}
|
|
p = p->next;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
static int get_nth_ancestor(const char *name, int len,
|
|
unsigned char *result, int generation)
|
|
{
|
|
unsigned char sha1[20];
|
|
int ret = get_sha1_1(name, len, sha1);
|
|
if (ret)
|
|
return ret;
|
|
|
|
while (generation--) {
|
|
struct commit *commit = lookup_commit_reference(sha1);
|
|
|
|
if (!commit || parse_commit(commit) || !commit->parents)
|
|
return -1;
|
|
memcpy(sha1, commit->parents->item->object.sha1, 20);
|
|
}
|
|
memcpy(result, sha1, 20);
|
|
return 0;
|
|
}
|
|
|
|
static int peel_onion(const char *name, int len, unsigned char *sha1)
|
|
{
|
|
unsigned char outer[20];
|
|
const char *sp;
|
|
const char *type_string = NULL;
|
|
struct object *o;
|
|
|
|
/*
|
|
* "ref^{type}" dereferences ref repeatedly until you cannot
|
|
* dereference anymore, or you get an object of given type,
|
|
* whichever comes first. "ref^{}" means just dereference
|
|
* tags until you get a non-tag. "ref^0" is a shorthand for
|
|
* "ref^{commit}". "commit^{tree}" could be used to find the
|
|
* top-level tree of the given commit.
|
|
*/
|
|
if (len < 4 || name[len-1] != '}')
|
|
return -1;
|
|
|
|
for (sp = name + len - 1; name <= sp; sp--) {
|
|
int ch = *sp;
|
|
if (ch == '{' && name < sp && sp[-1] == '^')
|
|
break;
|
|
}
|
|
if (sp <= name)
|
|
return -1;
|
|
|
|
sp++; /* beginning of type name, or closing brace for empty */
|
|
if (!strncmp(commit_type, sp, 6) && sp[6] == '}')
|
|
type_string = commit_type;
|
|
else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
|
|
type_string = tree_type;
|
|
else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
|
|
type_string = blob_type;
|
|
else if (sp[0] == '}')
|
|
type_string = NULL;
|
|
else
|
|
return -1;
|
|
|
|
if (get_sha1_1(name, sp - name - 2, outer))
|
|
return -1;
|
|
|
|
o = parse_object(outer);
|
|
if (!o)
|
|
return -1;
|
|
if (!type_string) {
|
|
o = deref_tag(o, name, sp - name - 2);
|
|
if (!o || (!o->parsed && !parse_object(o->sha1)))
|
|
return -1;
|
|
memcpy(sha1, o->sha1, 20);
|
|
}
|
|
else {
|
|
/* At this point, the syntax look correct, so
|
|
* if we do not get the needed object, we should
|
|
* barf.
|
|
*/
|
|
|
|
while (1) {
|
|
if (!o || (!o->parsed && !parse_object(o->sha1)))
|
|
return -1;
|
|
if (o->type == type_string) {
|
|
memcpy(sha1, o->sha1, 20);
|
|
return 0;
|
|
}
|
|
if (o->type == tag_type)
|
|
o = ((struct tag*) o)->tagged;
|
|
else if (o->type == commit_type)
|
|
o = &(((struct commit *) o)->tree->object);
|
|
else
|
|
return error("%.*s: expected %s type, but the object dereferences to %s type",
|
|
len, name, type_string,
|
|
o->type);
|
|
if (!o->parsed)
|
|
parse_object(o->sha1);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int get_sha1_1(const char *name, int len, unsigned char *sha1)
|
|
{
|
|
int ret, has_suffix;
|
|
const char *cp;
|
|
|
|
/* "name~3" is "name^^^",
|
|
* "name~" and "name~0" are name -- not "name^0"!
|
|
* "name^" is not "name^0"; it is "name^1".
|
|
*/
|
|
has_suffix = 0;
|
|
for (cp = name + len - 1; name <= cp; cp--) {
|
|
int ch = *cp;
|
|
if ('0' <= ch && ch <= '9')
|
|
continue;
|
|
if (ch == '~' || ch == '^')
|
|
has_suffix = ch;
|
|
break;
|
|
}
|
|
|
|
if (has_suffix) {
|
|
int num = 0;
|
|
int len1 = cp - name;
|
|
cp++;
|
|
while (cp < name + len)
|
|
num = num * 10 + *cp++ - '0';
|
|
if (has_suffix == '^') {
|
|
if (!num && len1 == len - 1)
|
|
num = 1;
|
|
return get_parent(name, len1, sha1, num);
|
|
}
|
|
/* else if (has_suffix == '~') -- goes without saying */
|
|
return get_nth_ancestor(name, len1, sha1, num);
|
|
}
|
|
|
|
ret = peel_onion(name, len, sha1);
|
|
if (!ret)
|
|
return 0;
|
|
|
|
ret = get_sha1_basic(name, len, sha1);
|
|
if (!ret)
|
|
return 0;
|
|
return get_short_sha1(name, len, sha1, 0);
|
|
}
|
|
|
|
/*
|
|
* This is like "get_sha1_basic()", except it allows "sha1 expressions",
|
|
* notably "xyz^" for "parent of xyz"
|
|
*/
|
|
int get_sha1(const char *name, unsigned char *sha1)
|
|
{
|
|
int ret;
|
|
unsigned unused;
|
|
|
|
prepare_alt_odb();
|
|
ret = get_sha1_1(name, strlen(name), sha1);
|
|
if (ret < 0) {
|
|
const char *cp = strchr(name, ':');
|
|
if (cp) {
|
|
unsigned char tree_sha1[20];
|
|
if (!get_sha1_1(name, cp-name, tree_sha1))
|
|
return get_tree_entry(tree_sha1, cp+1, sha1,
|
|
&unused);
|
|
}
|
|
}
|
|
return ret;
|
|
}
|